3:42.66: how Josh Kerr took down the oldest record in middle-distance running

Some world records are broken by accident, on a good night. The men’s mile record was not that kind of record. Hicham El Guerrouj ran 3 minutes 43.13 seconds in Rome in 1999, and for 27 years nobody came close enough to make it feel vulnerable.

On 18 July, in front of a crowd of around 60,000 at the London Diamond League, Josh Kerr ran 3:42.66.

He won by more than three seconds. The American Yared Nuguse, one of the finest milers of his generation, finished second in 3:45.69. Kerr’s own previous best, from 2024, was 3:45.34, meaning he took almost two and three-quarter seconds off his personal record in a single race.

Project 222

What made the run unusual was that Kerr told everyone it was coming.

In March, he announced that he would attempt the record in London in July. He called it Project 222, after the number of seconds he needed: 3:42 is 222 seconds. He set himself three conditions, according to an interview cited by Wikipedia: the attempt had to be a legal race rather than a time trial, it had to be in the UK, and he would commit his whole season to it, because, in his words, “this isn’t a record that you can steal.”

He then built everything around that one evening. Kerr raced only two 800 m races in the months before London. He spent five weeks training at altitude in Albuquerque, New Mexico, at around 1,600 metres, and according to reporting on his preparation he converted his bedroom into an altitude chamber, sleeping at a simulated 8,200 feet. In a time trial during the build-up, he ran 1,200 m in 2:42.45.

On the night, two pacemakers held him on record pace through most of the race before stepping aside. The last lap was his alone.

The rest of the season

A world record would have made any season. Kerr’s kept going.

In March, before the record attempt, he won the world indoor 3000 m title in Toruń, Poland, his second. At the Commonwealth Games in Glasgow on 1 August, he won the mile, an event restored to the Games for the first time since 1966, in 3:54.12, pulling away from Cameron Myers of Australia and his fellow Scot Jake Wightman over the final 200 metres of a slow, tactical race. Kerr described it as the championship he had circled on his calendar, run in front of a home crowd.

And in September, at the inaugural World Athletics Ultimate Championship in Budapest, a $10 million invitational for the world’s best, Kerr, invited into the 1500 m field alongside Jakob Ingebrigtsen, won that too.

What made it work

There is a useful lesson in how Kerr approached the record, beyond the physiology. He chose one target, announced it, and organised everything else around it, including racing very little in the months beforehand, when many athletes would have chased fitness through competition.

That focus is not the same as doing more. Kerr’s build-up was defined as much by what he left out as by what he added: fewer races, a narrower goal, and the conditions (a home crowd, a legal race, pacemakers who knew the plan) that gave him the best possible chance on one specific night.

El Guerrouj’s record survived the arrival of carbon-plated spikes, new pacing technology and more than two decades of professional track running. It took an athlete willing to stake an entire season on 222 seconds to finally move it.